Kingdom Hearts: Between Light and Darkness
by Amarielah
Summary: When Heartless attack the Death Star, Princess Leia Organa and Darth Vader find themselves in Traverse Town, and form a temporary alliance in an effort to restore their world. While searching for answers, they get drawn into the fight for Kingdom Hearts. Star Wars/Kingdom Hearts/Disney/Final Fantasy crossover.
1. Chapter 1

Summary: When Heartless attack the Death Star, Princess Leia Organa and Darth Vader find themselves in Traverse Town, and form a temporary alliance in an effort to restore their world. While searching for answers, they get drawn into the fight for Kingdom Hearts. Star Wars/Kingdom Hearts/Disney/Final Fantasy crossover.

Disclaimer: I don't own Star Wars, Kingdom Hearts, any Disney properties, or any of the Final Fantasy games.

Timeline and canon notes: Takes place before and during KH1, with changes due to the presence of the Star Wars characters. The Final Fantasy characters come from their original games, because I think they're more interesting that way, with the exception of the kids from Destiny Islands (though a FFX version of Tidus is probably gonna show up at some point). Some Disney worlds that didn't show up in the games might make an appearance as well.

* * *

Leia remembered how the Heartless consumed the Death Star. Looking back, she suspected that they had been drawn there by the smothering darkness that engulfed the so-called battle station. Perhaps, even, by the void left behind by so many lives being snuffed out with Alderaan.

She remembered sleek black bodies and yellow, glowing eyes, looking straight into her heart. Seeing the despair that she held in check behind a wall of determination. She had felt their hunger.

She had turned them away, somehow, before she'd been swallowed by what seemed like endless darkness.

And then she'd woken up in Traverse Town.

* * *

She wasn't happy to find that Vader was there too, his dark form like a shadow from her nightmares. But he was about as congenial as he ever got.

"You and I have a common goal, your highness," he said, his hulking form comically incongruous against the backdrop of the quaint little bistro, a wooden chair groaning in protest under his weight.

Leia scoffed. "Is this the part where you suggest we work together to restore our world, Lord Vader?"

"You're a resourceful young woman," he said, by way of confirmation.

"And _you're_ a monster," she replied coldly. She tried to push back the memories of him standing impassively above her as she screamed in agony, of him holding her in place as she had watched Alderaan burn.

"Perhaps," he said easily. "But I fail to see how that's relevant to the situation at hand."

Leia felt her stomach churn in revulsion, even as she said, "I suppose I have little choice."

She was sure that she wasn't imagining the smugness in his voice. "I'm glad you see the wisdom in this, your highness. These are...unusual times."

In spite of herself, Leia felt a smirk tugging at her lips. "I see that your talent for understatement is as impressive as your talent for theatrics."

A hiss of breath, which may or may not be a sound of amusement. "I'm glad that I can be of service," he said.

* * *

"You will return my lightsaber or suffer the consequences."

"Consequences, huh?" Yuffie didn't look even remotely intimidated. "Like that thing where you choke people with your magic?" She grinned like a lothcat. "You just try it, Darth Scuba. I don't think you'd like to try a level-three Fire spell on for size."

Leia sighed, wondering if she should try to intervene, before a new voice piped in.

"Just give the man his damn laser sword back, ya brat. You'll only hurt yourself with it, anyway." Cid took a drag of his cigarra. "And give me back my Fire materia while you're at it."

"Nuh-uh," Yuffie protested. "I got 'em both fair and square. It's not my fault that you two weren't paying attention."`

"Your ability to approach me undetected is most impressive," said Vader. "But my patience is wearing thin."

Cid took his cigarra out of his mouth and tossed it to the pavement, stamping on it. "If you don't give 'em back now, I'll get Aerith to get 'em from you later."

Leia almost cringed on the girl's behalf. She'd never met anyone as aggressively _nice_ as Aerith, and yet with such a force of personality. She'd considered asking her to join the Alliance more than once, though she knew she'd be turned down for sure.

Yuffie cringed on her own behalf, then sighed. "Okay, fine. Just...don't tell her about this." She tossed the lightsaber to Vader, who caught it telekinetically, then threw a small red orb to Cid.

"Showoff," muttered Cid, putting the orb into a slot on his wristband.

"According to the princess, that's the least of my flaws," replied Vader, hooking the lightsaber onto a clip on his belt.

" _The_ _p_ _rincess_ is standing right here," said Leia. She wondered then what a level-three Fire spell looks like, and what sort of damage it could deal to Vader's suit.

"Now don't you two start," said Cid. "I've got a new ship design I thought you might be interested in takin' a look at, Vader. Might actually be flyable."

"Certainly," said Vader.

"Also, don't threaten Yuffie again. She's a thief and a brat, but she doesn't deserve to die for it. And it'd be a shame to get rid of one of the few people in this shithole with half an understandin' of machines."

Leia sensed the danger in the air as Vader said, "It is unwise to underestimate my power, Highwind."

Cid snorted. "Sure, you're powerful. But so 're Aerith and Squall. And me, if I get serious."

"I wouldn't worry," Leia said, glaring pointedly at the Sith Lord. "Lord Vader wouldn't sink so low as to murder a child. And certainly not over a matter that's so easily resolved without violence."

"That true, Vader?" asked Cid.

It was strange, but lately Leia had been...sensing things. Heartless approaching, and other people's emotions. When she'd first met him, Merlin had said that she had the potential to become powerful with magic, and she was starting to suspect that he wasn't entirely off-base. However much the thought unnerved her.

Right now, she was sure that she can sense that her words had caught Vader off-guard.

"...Her highness is correct," he said, at length.

"Well then, that's settled." Cid started walking to the First District. "Let's get started."

* * *

"It must be frustrating for you," said Leia later, when the two of them were alone in the Red Room of the hotel. It had become their make-shift war room.

"There are many things I find frustrating at present, your Highness."

Leia rolled her eyes, knowing that he was being deliberately obtuse. "I mean, being surrounded by people who are too powerful to push around. People who refuse to accept your authority."

"Frustrating is not the word I would use," he said, and she noted the lack of a not-so-veiled threat directed at her. For the first few weeks, he'd constantly alluded to the fact that he could kill her with a thought. Perhaps he'd finally realized that the threats meant nothing when it was obvious that he needed Leia for some future purpose - though she wasn't even sure he knew what it was yet. If not for his conviction that she'd be of use to him, he would've killed her already.

"Then what word _would_ you use?" she asked.

"Motivating."

Ah. So he wanted to get to the matter at hand. "Subtle," she said.

"Subtlety is not a trait I've ever possessed."

"How completely unsurprising." She crossed her arms over her chest. "I suppose your meeting with Cid was fruitful, then."

"Yes," he said. "These "gummi ships" rely on bizarre technology, but we've managed to come up with a functional design. With the right materials, I may even be able to build something like a hyperdrive."

Leia still marveled at the fact that Cid and Vader actually seemed to tolerate each other – and perhaps even enjoy each other's company – having found a common purpose in cobbling together a vessel from technology that neither of them were familiar with. If nothing else, Vader had yet to choke the man even once, in spite of Cid's complete lack of anything resembling deference.

"When do we leave, then?" she asked.

"It should take no more than two weeks to complete," he replied. "Once we've managed to salvage all the necessary parts, that is. And how quickly that goes depends on how cooperative the Moogles are."

Leia sighed. The Moogles were the true experts on all things gummi technology, but weren't the sort to part with their knowledge for free. In lieu of money, Vader had at first attempted to secure their cooperation with force.

It had been a spectacular failure, resulting in Squall summoning a powerful ice-controlling being called Shiva, and the Moogles raising their already steep regular rate by 50%. Afterward, she remembered how Vader had muttered something about them being worse than Jawas. His pride had been severely bruised ever since, which had been the only good thing to come out of the whole debacle.

"We already owe them a lot of money," said Leia.

"Money which we cannot get to them until we have a working ship," he retorted. A pause, and then, "There is something else I wish to discuss with you, your highness."

She gestured for him to go ahead.

He said nothing for a few moments, his mechanical breathing filling up the silence. "I believe that the Force is with you."

For some reason, she wasn't surprised. She wasn't entirely sure what the Force even was, but the words have a ring of truth to them. "I see," she said.

"I can train you in the ways of the Force," he continued. "As my apprentice, you would become more powerful than you can possibly imagine."

Leia rolled her eyes. "And then when we restore our world, we'll defeat the Emperor together and rule the Galaxy?"

"That was going to be part of my offer, yes." Though she sensed he would have waited to say that part until she was already indoctrinated in his religion. "Our goals may not be as different as you think, princess, even if we disagree on the finer details."

The "finer details" being whether or not the galaxy should remain a totalitarian dictatorship, she suspected. "Well, I'm not interested," she said. "I've already received an offer to be trained by Merlin, and I think he's a far better option for me."

Vader's outrage was immediate. "That delusional old man will do nothing but hold you back."

"I disagree," she said, smiling coldly. "Actually, I think I'm going to go tell him about my decision right now. He's sure to be thrilled."

She stood up and began to leave, half expecting him to stop her. But even though his rage was palpable, all he said was, "Be mindful of the Heartless."

She stopped at the door. "They're attracted to _you_ , Lord Vader, not me. I'm sure that I'll be just fine."

His anger clung to her as she finally made her way out of the hotel. She took it as a victory.


	2. Chapter 2

Disclaimer: I don't own Star Wars, Kingdom Hearts, or anything by Disney and Square Enix.

Note: This chapter was hella fun to write. I really love putting Vader out of his depth.

* * *

As much as it irked Vader to admit it, he found the Aerith woman unnerving. He could barely sense her in the Force, as though she was millions of lightyears away. And yet, when she looked at him, it was as if she's seeing straight through his armor and into his very soul. Although he found it shameful, he tried to avoid her as much as possible

Unfortunately, she had a habit of running into him. Especially when he was in a particularly unpleasant mood.

Admittedly, it had been a very long time since Vader had been in a _pleasant_ mood. But an extended conversation with the Princess usually left him with a strong desire to choke someone. Indeed, the Princess would likely already be dead under normal circumstances.

But these are far from normal circumstances.

He knew that she was to play a vital role in helping to restore their world.

He was also certain that the Force is strong in her. Given all the rage she carried within her, it would be a simple enough task to mold her into a useful servant - as he'd done with dozens of Inquisitors. And yet, there were obstacles everywhere. Many of which that he could never have foreseen.

Like the woman standing before him now, smiling.

"Hello, Mr. Vader," she said.

He nodded once in acknowledgment.

"You seem to be on your way to do something important," she continued, walking closer. "And you also seem very grumpy."

"How observant of you," he said, bristling at the word "grumpy". Had his dignity not already been impugned upon enough?

"Yup. Totally grumpy."

The little patience he had was wearing thin, so he said, "What is it that you want?"

Her smile widened. "I just wanted to say hello."

He couldn't sense enough from her to know if she was lying, so he tried to reach out even further with the Force. But her mind was beyond his grasp, giving him nothing but psychic static. It did nothing to improve his disposition.

"It's because I'm dead," she said brightly.

Vader startled out of his intense concentration, frowning under his mask. "What do you mean?"

"The reason why your powers don't react to me like normal people – it's because I'm dead." Her smile was very sweet. "I get the feeling that you've been wondering about it for a while."

Memories stirred in the depths of Vader's mind, not entirely welcome for the remnants of Anakin Skywalker that resurface with them. Of Mortis, and the apparition who may have been Qui-Gon Jinn. "How is it possible for you to be here if you're dead?" he asked.

"I'm not entirely sure myself," she admitted easily. "I think it might have to do with the fact that I managed to retain my identity in the Lifestream, and that I helped the others reach this place when the Heartless attacked." Her smile became apologetic. "I'm sorry. This probably doesn't mean much to you."

Actually, it all sounded very familiar. He thinks that the "Lifestream" was an apt enough name for the Living Force. "How were you able to maintain your identity in this Lifestream?"

She let out a little giggle and clasped her hands behind her back. "I don't really remember that part either. Everything was much clearer when I was actually in it, you know?"

He could feel his irritation rising, and decided that now would be a good time to leave her presence. Vader was no coward. While he could indeed sense the immense power that the girl possessed, even distant as she was to him in the Force, it was not her potential retribution that he was wary of.

Rather, it was the fact that using the Dark Side drew the Heartless to him like rancors to raw meat. Of course, the Heartless were unusually attracted to him even when he didn't use the Dark Side, but using it made him especially vulnerable to their attempts to consume him. Even through the rush of power and control, he could feel them gnawing at the edges of his soul, eating away at what little of him was still human. It had motivated him to rein in his anger in a way he hadn't in years. Or at least to avoid situations that made him angry enough to tap into the Dark Side instinctively.

"Then you are of no use to me," he said, whirling around to walk in the opposite direction. He'll have to go to Merlin's through the Third District, it seems.

The Third District, which was crawling with Heartless.

She didn't follow him.

* * *

He ignited his lightsaber the moment he entered the Third District, bile rising to the back of his throat as the cloying presence of Heartless enveloped him. It was not unlike how he'd felt years ago as a Jedi when first confronted with places steeped in the Dark Side. And yet, even then, the Dark Side had held a certain allure – a promise of power.

The Heartless hold no such appeal.

Before they even came on the offensive, he could already feel them looking for cracks in his mental defenses, demanding entry into the very depths of his soul. Their hunger for him was voracious.

He struck down one of the little ones as it emerged from shadows on the pavement, and began to his slow progression towards the door of Merlin's Keep. The Force at least could interact with Heartless that existed in corporeal form, and he used it to repulse the flying beasts that approached him, lashing out with his lightsaber at those that managed to breach his defenses.

It was a struggle not to call on the power of the Dark Side as his anger at the creatures, and at his own weakness, began to rise, beckoning him with its promise of swift and sure victory. Only the thought of becoming one of them – a death in all but name, or worse, with all individuality consumed by mindless hunger – that stop[ed him from giving in.

He couldn't deny the relief he felt when he finally reached the red door leading to his destination, feeling Leia's presence beyond it. He had hoped to arrive after she was no longer there, but he supposed it made little difference in the end.

He Force-jumped across the shifting rocks floating in the moat, and soon reached the ramshackle house which the old wizard had taken up as his residence. He didn't bother to announce his entry as he pushed aside the piece of fabric that served as a make-shift door.

He found that Leia and Merlin were sitting at a small round table, drinking tea. Or at least, they had been; Leia set down her cup in order to properly glare at him.

"I don't recall inviting you to join us," she said.

"I did not come here to join your tea party," he replied. "I wish to speak to the old man. Alone."

Merlin's frown reminded Vader all too much of severak Jedi Masters, which only made his irritation grow. "Well, this _old man_ has no desire at all to speak with _you_ alone. Now leave before I turn you into a...a rabbit!"

"I will end you before you can even try," Vader said.

Merlin stood up in a huff, knocking over his teacup in the process so that it shattered on the floor. "Oh, yes, yes – you're very frightening. I still expect you to leave me and my pupil in peace!" He noticed the broken cup and stamped his foot. "Hang it all! That was one of my last ones!"

Leia stood as well, crossing her arms over her chest. "What exactly do you hope to accomplish here, Vader? I've already made my decision, and acting like a thug is not going to make me change my mind."

Vader allowed some of his anger to flow out into the Force – a Jedi trick,which rankles him. But there was no denying that it had been very helpful in managing more delicate situations since arriving in this Force-forsaken place. "I will not harm him, your highness. I only wish to speak with him."

"Harm me?" exclaimed the wizard. "Hah!"

"Whatever you have to say, you can say it with me here," said Leia.

"Very well." Vader raised his finger and pointed at Merlin. "It is not her Highness' destiny to be your apprentice."

Leia rolled her eyes. "I don't believe in destiny, Lord Vader."

"Well, _I do_ ," said Merlin. "But I see things very differently, indeed. Why, I've felt for weeks now that the Princess was going to accept my tutelage, and I was right! This "Force" nonsense may be all well and good in the world you come from, but it's next to useless against the Heartless. Just look at the way they swarm about you, like, like – the sorts of things that swarm about!"

"It's unwise to underestimate the Force, old man." Vader made a fist to emphasize the point.

"And it's just as unwise to overestimate it!" Merlin snapped back. "I just bet you're the sort who thinks your powers can solve all of your problems!"

"Enough of this," snapped Leia. "The decision is mine and mine alone." She glared hard at Vader. "If learning the ways of the Force will make me like you, then I have no interest in it. Accept my choice, Lord Vader, or our partnership is at an end."

Vader seethed, wishing very much that he could kill something or someone at that moment. But again, he let his emotions flow out into the Force; he couldn't afford to lose control. At length, he said, "As you wish, you Highness. But I'm concerned that you're making a grave mistake."

Leia smiled tightly. "Well, we'll find out if that's the case soon enough, won't we?"

"Now then, that's all settled," said Merlin, throwing up his hands, and Vader felt his cloak being tugged towards the door. "I insist that you leave us be. Out, out, out!"

Vader warded off the invisible hands with a push of the Force, but stalked out of the house without further protest. Merlin may have won the battle, but he had hardly won the war.

He had a ship to build, in any case.


End file.
